Not exactly.
If it is optional work, such as a check/repair, then you obviously only tell it to do that at the appropriate time, and you can stop if by echoing 'idle' to 'resync_action'.
If there is work the needs to be done, the md will try to do it straight away. The best you can do is slow it down substantially. If you echo '1' to /sys/block/mdX/md/sync_speed_min then the resync will be very very slow. When 'out of hours' comes around, write a bigger number and it will go faster again.